MedlinePlus Medical Encyclopedia:Chorionic villus sampling

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Chorionic villus sampling - series: Normal anatomy

Chorionic villus sampling - seriesIllustrations:

Normal anatomy

Procedure, part 1

Procedure, part 2 - transcervical

Procedure, part 2 - transabdominal

Results

Chorionic villi are microscopic projections that line the chorion, the outermost layer of the embryonic sac. Surgeons sample these projections for genetic testing because they contain the same genetic material as a fetus.

If you are at risk for delivering a baby with genetic abnormalities, your health-care provider may recommend this prenatal test, which is performed at 10 to 12 weeks gestation to find out a fetus' genetic makeup.

Update Date: 9/19/2006

Updated by: Audra Robertson, MD, Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, MA. Review provided by VeriMed Healthcare Network.

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